Screw-rolling machine



Sept. 14,1926.

1,600,112 J. HELLER SCREW ROLLING MACHINE Filed Feb. 27, 1926 2 Sheets-Sheet 1 IHVENTOR uuuus HELLER BYHAS ATTORHEYJ 1..

Sept. 14 1926.

' LGWXITZ J. HELLER SCREW ROLLING MACHINE Filed Feb. 27, 1926 2 Sheets-Sheet 2 mvmrb/e JUL/U5 HELLER BYHIS Afro/mm Patented Sept. 14, 1

UNITED JULIUS HELLER, OF VIE STATES PATENT OFFICE.

NNA, AUSTRIA, AS S IGNOR TO THE FIRM SCHRAUBEN- UNI) A. URBAN 8c SOHNE, 0

Application This invention relates machines in which the thread F VIENNA, AIJ'S'JZ'RIA SCREW-ROLLING MACHINE.

to screw rolling 1s rolled into the shank by two rolling dies having cut into their adjacent sides the grooves required for producing the thread. The two rolling dies are reclprocated but in opposite directions.

at equal speed. The shank of the screw brought into position between the two rolling dies is thus rotated by these dies around geometrical axis. machines it 1s necessary the displacement of the to the rolling which otherwise result in an In these to compensate for shank metal due displacement would increase of the outer diameter of the threaded part of the bolt beyond the For this purpose a chip while this is being in many cases screw head 1s shape.

For this purposechipping and pointing diameter of is cut off the thread rolled and in most cases knives are provided which during rolling are moved radially and relatively to the geometrical axis of bolt or screw according crease of the outer ax1ally respectively the to the gradual indiameter of the thread.

The required movement is imparted to the chipping lmives arranged diametrically opposite each other relatively to the geometrical axis of the bolt or screw and if desired also to the pointingkmfe by securing these knives to which Speeds but in opposite are moved at all times with carriers or slides ual directions so tiat these knives approach or recede from the geometrical axis of the by equal distances. knife carriers are rolling dies.

bolt simultaneously These movements of the derived from one of the Now in order to prevent the rolling dies from coming into contact with the knives which would be detrimental to the rolling dies as well as to the knives and would give rise to'frequent interruptions of operation, according to the present invention, guiding ribs for the knives are rigidly secured to the rolling dies which ribs. enclose between them the knives and reliably prevent any lateral distortion or vibration of the knives which mightre'sult from the lateral strains exerted by the blank during the'cutting.

the shank body.

have at every other relatively to filed February 27, 1926, Serial No. 91,133, and in Austria January 18, 1926.

In the drawings Fig. 1 is a longitudinal section and In the constructional form shown by way of example it is assumed that the rolling dies 1, 2 are nicely adjustably mounted in sup- I ports 3, 1 and are reciprocate'd for instance by racks and pinions -in guides of the machine frame in such a manner that they moment equal but opposite speeds. The stroke of the rolling dies is so selected that at each end of the stroke the one has fully passed the other. The bolt blanks are rought into position between the rolling diesbefore the beginning of the working. stroke so that the blank apart from a slight axial movement due to the pitch of the'thread has imparted to it only a rotary movement around its geometrical axis.

In a casing 5 fixed on the machine frame two knife carriers 6, 7 are adjustably secured to slides 8, 9 movable parallel to the direction of movement of the rolling dies. To the knife carriers the chipping knives 10, 11 are secured, the chipplng edges 16,

17 of which are diametrically opposite each the geometrical axis of the blank. The slides 8, 9 are mechanically connected with each other in such a manner that'they always move through equal distances, but in opposite directions. This mechamcal connection comprises for nstance a pinion 14 and two racks 12, '13. A rocking movement is imparted to the pinion 14: in accordance with the reciprocati'ng movement of the knives. This rocking movement is derived from one of the rolling die slides, say 31. For instance a lever- 19 journalled in the casing 5 one of the ends of the lever provided with a roller running along a cam 20 securedto the slide 31 and the other end of the lever carries a toothed sector engaging into a pinion 21 on' the shaft of the pinion 14.

While during the working stroke of the as the shank of the bolt.

9 are moved simultaneously from opposite sides towards the blank, rotating around its geometrical axis, through the medium a of the lever 19, the toothed sector, the toothed wheels 21 and 14 and the racks 12, 13 for cutting periphery of the thread being formed on opposite sides thereof, so that finally the finished thread hasthe same outer diameter When the thread is dies still continue their movements, the en of the lever 19 provided with the roller running over the part ofthe cam inclined at a greater angle and the slides 8, 9 are forced apart by springs 32 interposed between them and the frame 5; thus th engagement with the finished bolt or screw and the latter is released and drops from the machine. Then the'rolling dies begin the idle return stroke and the slides 8, 9 with the knives 10, 11 are moved towards each other so that at the end of the return stroke a fresh blank may be inserted between them. This is secured by the slightly inclined part of cam 20 at the other end of the same.

f it is desired to pointthe screw simultaneously wit taking off the chip either a separate pointing knife may be used or a pointing edge 18 may be provided .on one of the chipping kniyes say 10. In an case the pointing edge must make during t e rolling of the thread a movement parallel to the geometrical axis of the blank and the stroke of this movement must correspond to the axial movement of the blank in the, course of the rolling of the thread. This movement of the'edge 18 is derived from one of the finished the rolling rolling die slides, preferably from the slide- 1 or the support 3, a cam 22 being secured to the same on which runs against the action of a suitable spring 33 a roller on a kmfe carrier guided parallel to the axis of fthein by t e the blank in the in the casing 5. In order to prevent the knives from bein laterally-distorted or vibrated b the rapid movement of the rolling dies and ticularly b frame of the'machine or more parthe lateral strains exerted upon blankowin to the cutting of! of the-chip whereby the inives might come 'mto contact with the rolling dies which be constructed as shown in Fi I washer plates adjustably and rigidly secured would be detrimental to both knives and the rolling dies and would lead to frequent interruptions of operation, guiding ribs 41, 42 are r gidly connected to the rolling dies which ribs guide the knives laterally and thus prevent any lateral distortion or. vibration of the same.

olf uniformly a chip from the outer carries the roller e knives come out; of

upon they can be These guiding ribs-may gs. 1 and 2 as in the rolling die slides, or these washer plates may be mounted on the rolling dies themselves and fixed in position by any suitable means, as shown in Figs. 4 and 5, if the rolling dies are too broad for the screws to be rolled. a v

It is preferable to mount the pointing edge 18 on one of the chipping knives say 10. The carrier 7 of this knife must then make besides the movement radial to the geometrical axis of the blank required for cutting off the chi s also a movement parallel to this axis. his can be effected by securing the knife carrier not directly to 1ts slide 9, but to a transverse slide 23 which is guided parallel to the axis of theblank and secured to the slide 8, The transverse slide then is acted upon by the spring 33.

As the rolling dies begin their working stroke the pointing knife or edge 18 of the knife carrier 7 is moved towards the end of the blank and turns the samedown in the course of the working stroke. At the end of the working stroke the chipping knives recede fromeach other and the pointing edge 18 is moved away from the blank simultaneously so that the latter is released and may drop freely out of the machine. Duringthe idle return stroke of the rolling dies the pointing knife is returned into its initial position. a For easily and readily exchanging the ife carriers and'for nicely adjusting the knives, the knife carrier is adjustably secured to the associated; slide 8, 9 or to the slide 8 and the transverse slide 23'by means of clamping screws and elongated holes and furthermore the knife .carriers are held between adjusting screws 25 on the slides 8, 9

Or on the slide 8 and the transverse slide 23.

running on the cam 22 and and removing them from the slides wherereplaced by others and also the knife carriers 6, 7 may be adjusted without difficulty. e The exchange of the cams 20, 23 for varying the thickness of the chip and the pointing is just as simple because also these parts are screwed to the slide 31 or support 3 and are readily accessible- The entire arrangement' is very simple compact cheap and reliable in operation-an permits to easily and rapidly remove the parts for sharpening or exchange because the casing 5 is fixed in the frame on the front side and also permits a ve simple and exact adjustment. Fnally the arrangement is very durable because the movements which the knife make are only small and slow.

What I claim is I 4 1. In a screw rolling machine the combination of rolling dies adapted'to revolve a 126 carriers have t9 1,000,112 I a a screw blank interposed between them around its (geometrical axis, means adapted to move its eometrical axis, means adapted to move sai dies simultaneously in ogposite'direcsai dies simultaneously in opposite direc- ,tions with equal speeds, two chlppin knives tions, two chipping knives arranged diaarranged diametrlcally opposite eac other metrically opposite each other with relation with relation to the geometrical axis of the to the geometrical axis of the-said blank, said blank, slides one for each knife conslides one for each knife carr ing such chiptrolled by the rolling dies for moving such ing nives, means controlle by the rolling slides simultaneously in opposite directions dies for moving such slides simultaneously with equal speeds and washers, rigidly conin op osite direction, and guiding ribs conneoted to the said rolling dies and projectnecte to the said rol ing dies and projecting beyond such rolling dies towards the in beyond such rolling dies towards the said knives whereby the latter are laterally sald knives whereby the latter are laterally guided between the rolling dies.

guided between the rolling dies. In testimony whereof have afiixed my 2. In a screw rolling machine the combisignature. nation of rolling dies adapted to revolve a 1 screw blank interposed between them around JULIUS HELLER. 

